Patellofemoral Pain Syndrome (Runner's Knee)

What Is Patellofemoral Pain Syndrome?

Patellofemoral pain syndrome (PFP syndrome) is pain in and around the kneecap (patella).
PFP syndrome is also called "runner's knee."

Rest and exercises that stretch and strengthen the hips and legs can help PFP syndrome
get better.

What Causes PFP Syndrome?

Patellofemoral (pronounced: peh-tel-oh-FEM-er-ul) pain syndrome is an overuse
disorder. These happen when someone does the same movements that stress the knee
over and over again.

In PFP syndrome, repeated bending and straightening the knee stresses the kneecap.
It's most common in athletes.

Some people with PFP syndrome have a kneecap
that is out of line with the thighbone (femur). The kneecap can get out of line, or
wiggle as it moves along the thighbone, because of muscle weakness, trauma, or another
problem. If this happens, the kneecap doesn't glide smoothly over the thighbone when
the knee bends and straightens. The kneecap gets injured and this causes the pain
of PFP syndrome.

Who Gets PFP Syndrome?

Patellofemoral pain syndrome usually happens in people who do sports that involve
a lot of knee bending and straightening, such as running,
biking, and skiing.
It also can happen to people, particularly young
women, who do not do a lot of sports.

PFP syndrome is more common in women and happens
most often to teens and young adults.

Tight or weak leg muscles or flat feet can make someone more likely to get PFP
syndrome.

What Are the Signs & Symptoms of PFP Syndrome?

Patellofemoral pain syndrome causes pain under and around the knee. The pain often
gets worse with walking, kneeling, squatting, going up or down stairs, or running.
It may also hurt after sitting with a bent knee for a long time, such as in a long
car ride or in a movie theater.

Some people with PFP syndrome feel a "popping" or creaking after getting up from
sitting or when going up or down stairs.

How Is PFP Syndrome Diagnosed?

To diagnose patellofemoral pain syndrome, health care providers:

ask about physical activities

do an exam

Usually no testing is needed. Sometimes the health care provider orders an X-ray
or other imaging study to check for other knee
problems.

How Is PFP Syndrome Treated?

Someone with patellofemoral pain syndrome needs to limit or completely avoid
activities that cause pain. Sometimes a change in training is all that's needed. For
example, someone who usually runs hills to train can try running on a flat, soft surface
instead.

A person who has severe pain or pain that interferes with activity (for example,
if it causes a limp) needs to rest the knee until the pain is better.

For pain:

Put ice or a cold pack on the knee every 1–2 hours for 15 minutes at a time.
Put a thin towel between the ice and your skin to protect it from the cold.

You can take ibuprofen (Advil, Motrin, or store brand) or naproxen (Aleve, Naprosyn,
or store brand). Follow the directions that come with the medicine for how much to
take and how often. Do not take this medicine for longer than about 2–3 weeks.

An important part of the treatment for PFP syndrome is improving the strength and
flexibility of the legs, hips, and core muscles. Health care providers usually recommend
going to a physical therapist to make an
exercise plan that will help. The plan may include stretching,
squats, planks, lunges, and other exercises that improve strength and flexibility
of the legs and hips.

The health care provider might also recommend:

a knee brace

taping of the knee

special shoe inserts

It doesn't happen very often, but sometimes surgery is needed for PFP syndrome.

Can Someone With PFP Syndrome Play Sports?

Most people with PFP syndrome need to cut back or stop sports for some time. Follow
the health care provider's instructions on when it's safe for you to go back to sports.
This usually is when:

Hip, leg, and core strength is near normal.

Flexibility, especially in the hamstring muscle, has improved.

There's no pain with everyday activities, such as walking and going up/down stairs.

Any pain with activity is very mild and goes away within a few minutes of starting
the activity.

Looking Ahead

It can take months to years for the symptoms from PFP syndrome to get better. Following
an exercise plan given by the health care provider or physical therapist can help
the knee heal.